para·​thi·​on ˌper-ə-ˈthī-ən How to pronounce parathion (audio)
: an extremely toxic insecticide C10H14NO5PS

Example Sentences

Recent Examples on the Web The pesticides found in the highest amounts included chlorpyrifos, methyl parathion and DDT. Wired Staff, WIRED, 12 May 2004

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'parathion.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History


para- + thiophosphate + -on entry 1

First Known Use

1947, in the meaning defined above

Time Traveler
The first known use of parathion was in 1947

Dictionary Entries Near parathion

Cite this Entry

“Parathion.” Dictionary, Merriam-Webster, Accessed 28 Mar. 2023.

Medical Definition


para·​thi·​on ˌpar-ə-ˈthī-ən, -ˌän How to pronounce parathion (audio)
: an extremely toxic thiophosphate insecticide C10H14NO5PS

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